Future radio access networks (RANs) are going to be more centralized than today's RANs, at least partly, i.e. radio access points only perform part of the RAN protocol stack while the main part is performed centrally (see FIG. 1). This implies that a remote radio access point only performs part of Layer 1-3 of the RAN functionality while the remaining functionality is performed at a central processor. This central processor may be a virtual BS pool executed on top of a cloud-computing platform, as described, e.g., in “C-RAN The Road Towards Green RAN”, White Paper v2.5, October 2011, CMCC, or in P. Rost, C. J. Bernardos, A. De Domenico, M. Di Girolamo, M. Lalam, A. Maeder, D. Sabella, and D. Wübben, “Cloud technologies for flexible 5G radio access networks”, IEEE Communications Magazine, vol. 52, no. 5, May 2014.
The considered data rates in a centralized RAN (CRAN) environment may vary significantly depending on the underlying functional split and parameterization. For 100 base stations, the expected traffic may range from a few 100 Gbps in the case of a very low-layer centralization, to a few 10 Gbps for user-based centralization, and a few Gbps for Layer-2 centralization. Latency requirements will range from a few 100 microseconds in the case of lower-layer splits to a few milliseconds in the case of user-based centralization and Layer-2 centralization.